Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Numerical Study on Cavitation Flow and Noise in the Flow Around a Clark-Y Hydrofoil

Clark-Y 수중익형 주변 공동 현상에 의한 유동장과 소음 예측에 대한 수치적 연구

  • Ku, Garam (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Cheong, Cheolung (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Kim, Sanghyeon (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Ha, Cong-Tu (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Park, Warn-Gyu (School of Mechanical Engineering, Pusan Nat'l Univ.)
  • Received : 2016.01.23
  • Accepted : 2016.10.28
  • Published : 2017.02.01
Download PDF
⟨ Previous Next ⟩

Abstract

Because the cavitation flow driven by an underwater propeller corrodes the materials around it and generates a high level of noise, it has become an important topic in engineering research. In this study, computational fluid dynamics techniques are applied to simulate cavitation flow, and the noise in the flow is predicted by applying the acoustic analogy to the predicted flow. The predicted results are compared with measurement results and other predictions in terms of surface pressure distribution and the temporal variation in liquid volume fraction. The predicted results are found to be in good agreement with the measured results. The source of the noise attributed to the time rate of change in the liquid volume fraction around the hydrofoil is modeled as a monopole source, and the source of the noise due to unsteady pressure perturbations on the hydrofoil surface is modeled as a dipole source. Then the predicted noise results are analyzed in terms of directivity and SPL spectrum. The noise caused by unsteady pressure perturbations was dominant in the entire frequency range considered in the study.

프로펠러와 같은 수중운동체 주변에서 발생하는 공동 현상은 물체를 부식시키고 소음을 발생시키므로, 공학적 측면에서 중요한 문제로 다루어지고 있다. 따라서 본 연구에서는 Clark-Y 수중익형에서 발생하는 공동 현상과 이로 인한 유동 소음을 예측하였다. 공동 예측 결과를 정량적으로는 수중익형 표면의 압력 분포, 정성적으로는 수중익형 주변 공동의 체적분율 변화 양상을 이용하여 비교하였으며, 실험결과 및 선행 연구와 비슷한 경향을 가짐을 확인하였다. 이러한 공동에 의한 유동 소음을 예측하기 위하여 음향상사법을 이용하였으며, 시간에 따른 체적분율 변화를 단극자 소음원으로, 수중 익형 표면에서의 비정상 압력섭동을 이극자 소음원으로 모델링하였다. 소음 예측 결과는 SPL과 방향성을 통해 분석하였고, 계산된 전체 주파수 영역에서 비정상 압력섭동에 의한 소음원이 지배적임을 확인하였다.

Keywords

References

  1. Rayleigh, L., 1917, "VIII.On the Pressure Developed in a Liquid During the Collapse of a Spherical Cavity," Philosophical Magazine Series 6, Vol. 34(200), pp. 94-98. https://doi.org/10.1080/14786440808635681
  2. Rouse, H. and McNown, J. S., 1948, "Cavitation and Pressure Distribution: Head Forms at Zero Angle of Yaw," Iowa City: State University of Iowa, University of Iowa Studies in Engineering, Vol. 32, No. 420, pp. 1-70.
  3. Rouse, H., 1962, "Cavitation and Pressure Distribution: Head Forms at Angles of Yaw," Iowa City: State University of Iowa, University of Iowa Studies in Engineering, Vol. 42, pp. 1-25.
  4. Wang, G., Senocak, I., Shyy, W., Ikohagi, T. and Cao, S., 2001, "Dynamics of Attached Turbulent Cavitating Flows," Prog. Aerosp. Sci., Vol. 37, pp. 551-581. https://doi.org/10.1016/S0376-0421(01)00014-8
  5. Kunz, R. F., Boger, D. A., Stinebring, D. R, Chyczewski, T. S., Lindau, J. W., Gibeling H. J., Venkateswaran. S. and Govindan, T. R., 2000, "A Preconditioned Navier-Stokes Method for Twophase Flows with Application to Cavitation Prediction," Computers and Fluids, Vol. 29, pp. 849-875. https://doi.org/10.1016/S0045-7930(99)00039-0
  6. Seo, J. H., Moon, Y. J. and Shin, B. R., 2008, "Prediction of Cavitating Flow Noise by Direct Numerical Simulation," Journal of Computational Physics, Vol. 227, pp. 6511-6531. https://doi.org/10.1016/j.jcp.2008.03.016
  7. Kim, S. H., Cheong, C. U., Park, W.G. and Seol, H. S., 2016, "Numerical Investigation of Cavitation Flow Around Hydrofoil and Its Flow Noise," Trans. Korean Soc. Noise Vib. Eng., Vol. 26, pp. 141-147. https://doi.org/10.5050/KSNVE.2016.26.2.141
  8. Merkle, C. L., Feng, J. Z. and Buelow, P. E. O., 1998, "Computational Modeling of the Dynamics of Sheet Cavitation," Proceedings of the 3rd International Symposium on Cavitation, Grenoble, France, pp. 307-311.
  9. Song, K. J., Yu, H. R., Kim, D. H., Kim, C. K. and Park, W. G., 2005, "Cavitation Flow Analysis of Hemisphere Cylinder Affected by the Variation of Model Constants," Spring Conference of Korean Society of Computational Fluid Engineering, pp. 220-224.
  10. Klaus, A. H. and Steve, T. C., 2000, "Computational Fluid Dynamics," Vol. 3, Engineering Education System, United States, pp. 1-175.
  11. Launder, B.E and Spalding, D.B., 1974, "The Numerical Computation of Turbulent Flows," Computer Methods in Applied Mechanics and Engineering, pp. 269-289.
  12. Wu, J., Utturkar, Y., Senocak, I., Shyy, W. and Arakere, N., 2003, "Impact of Turbulence and Compressibility Modeling on Three-dimensional Cavitating Flow Computations," 33rd AIAA Fluid Dynamics Conference and Exhibit, p. 4264.
  13. Johansen, S. T., Wu, J. and Shyy, W., 2004, "Filter-based Unsteady RANS Computations," International Journal of Heat and Fluid Flow, Vol. 25, No. 1, pp. 10-21. https://doi.org/10.1016/j.ijheatfluidflow.2003.10.005
  14. Ruprecht, A., Helmrich, T. and Buntic, I., 2003, "Very Large Eddy Simulation for the Perdiction of Unsteady Vortex Motion," Conference on Modelling Fluid Flow : CMFF'03, pp. 767-774.
  15. Dowling, A. P. and Williams, J. E. Ffowcs, 1983, "Sound and Sources of Sound," Halsted Press, New York, pp. 154-157.
  16. Kim, J. and Lee, J. S., 2015, "Numerical Study of Cloud Cavitation Effects on Hydrophobic Hydrofoils," International Journal of Heat and Mass Transfer, Vol. 83, pp. 591-603. https://doi.org/10.1016/j.ijheatmasstransfer.2014.12.051